Discipline: Biological Sciences
Subcategory: Plant Research
Delecia Utley - Howard University
Co-Author(s): Janelle Burke, Howard University, Washington, DC
Dioecious plants are plants with male and female reproductive parts on different plants. Sex ratio in dioecious plants is an issue still being explored amongst botanist. The sex ratios in dioecious plant populations are often close to a 1:1 ratio, or are male biased due to gender-specific differences. Rumex acetosa (Polygonaceae) is a dioecious wind-pollinated plant in which females posses XX, and males XY1Y2 sex chromosome system. To resolve functional sex among R. acetosa plants, leaf material was analyzed, using a PCR-based technique involving a male-specific DNA marker, to determine the sex of the plants. The observed female bias sex-ratio obtained by molecular work was consistent with the view that Rumex populations show female bias, having 11 female individuals and 7 male individuals. Resource allocation has been an observed reason for the female bias in R. acetosa. Males allocate more resources during flower production, while females allocate more resources during seed production. To investigate resource allocation among gender, both the female and male population were split into two treatments of high nutrients and low nutrients. The high nutrient treatment consisted of 50:50 sand to soil mixture and watered using 20:20:20 K/N/P fertilizer. The low nutrient treatment consisted of 70:30 sand to soil mixture and watered with regular water. The above and below ground masses were observed between the different treatments and the sexes within the different treatments. There was significant difference between the weight of individuals in high versus low nutrient treatments (p-value: <.005). There was no significant difference between the sexes within the different treatments. Replication of this experiment with a larger sample size is necessary in order to get a better look at sex ratio and resource allocation among the female and male individuals in Rumex.R. acetosa abstract.docx
Funder Acknowledgement(s): NSF HBCU-UP DEB#1601031
Faculty Advisor: Janelle Burke, janelle.burke@Howard.edu
Role: I grew the plants, conducted the molecular work, collected the raw data from the nutrient treatments, and completed the data analysis with the assistance of my faculty advisor.